Nickel alloy and method of making the same



Patented Feb. 9, 1926.

UNITED, STATES PATENT OFFICE.

PAUL D. MERICA, OF NEW YORK, N. Y., ASSIGNOR TO THE INTERNATIONAL NICKELCOMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

NICKEL ALLOY AND METHOD OF MAKING THE SAME.

No Drawing.

This invention relates to nickel alloys and method of making the same,and particularly t0 alloys of aluminum and nickel or of aluminum andMonel metal, which is a trade name for a natural nickel and copper alloymade by The International Nickel Companv.

I have found that the addition of aluminum to nickel or nickel-bearingmetals, such as Monel metal, has a great effect on the physicalproperties thereof. The resulting alloy 'has a high tensile strength andis highly resistant'to erosion and corrosion. It is thereforeparticularly valuable for use in steam turbine blading or in otherapplica-- tions where these properties are desirable.

In the manufacture of this alloy, I take molten nickel or Monel metaland deoxidize it, preferably with magnesium. The deoxidized metal isthen mixed with molten aluminum in the proper proportions. To facilitatea thorough mixing, I pour the principal melt, that is, the nickel ornickelbearing metal, onto the aluminum. This pouring of the heaviermetal onto the lighter insures thorough mixing and uniform composition.i

The mixing of the metals produces a marked evolution of heat whichraises the temperature of the ladle considerably. I utilize this extraheat by allowing the molten alloy to stand for a period of three to fiveminutes, thus giving the impurities an opportunity to rise-to thesurface and separate from the metal. The amount of heat evolved isroughly proportional to the percentage of aluminum added.

The clean metal is then poured into ingots which are reduced to shapesby the processes usual in nickel and Monel metal practice.

The surface of the ingots must be removed;

prior to rolling, and with an aluminum content of under 3% or 4% thesurface may be chipped or planed olf. When the aluminum content ishigher, it is necessary to grind the ingots Application filed June 26,1923. Serial No. 647,911.

After heating and rolling, aluminum Monel alloys containing as much as5% aluminum can be machined with ordinary tools.

. The addition of aluminum increases both the hardness and tensilestrength of the metal. The best mechanical properties are obtained withaluminum between 3% and 5%, although amounts above 1% are effective. Theupper limit of the aluminum content depends largely on the propertiesdesired. Good results may be had up to 10%, although there is greatdifficulty in grinding and reducing ingots containing so much aluminum.If the aluminum content is increased above 17%, the alloy is verybrittle.

lVith an aluminum content between 3% and 5%, hot rolled rods may beproduced with a true proportional limit of as high as 80,000 pounds persquare inch, which Would be reduced by dead annealing at 1650 F. to notless than 60,000 pounds per square inch. High temperature tests showthat the alloy retains its strength very satisfactorily at 750 F., andin fact the percentage reduction in the proportional limit at thistemperature 'as compared with ordinary temperatures is less than in thecase of Monel metal. The resistance .to corrosion is as great as, orgreater than, in Monel metal.

The addition of carbon to the alloy between 0.1% and 0.5% exercises amarked effect in increasing the hardness and tensile strength.

While I prefer to use Monel metal, which is the natural alloy consistingof 68% to 70% nickel, a small percentage of iron and the remaindercopper, I may use nickel and copper in other proportions, as, forexample, 50% to 80% nickel and 20% to 40% copper, together with aluminumin the desired amount. The addition of 25% to 2.5% manganese is alsodesirable. Thealloy apparently is not greatly affected by the presenceof other metals in small amounts as may occur on account if impuritiesin the metals used.

\Vhile I have described the preferred e1nbodiment of my invention. itwill be understood that it is not limited thereto but may be otherwiseembodied within the scope of the following claims.

I claim:

1. The method of making nickel alloys. which includes deoxidizing theprincipal melt and then mixing it with molten aluminum.

2. The method of making nickel alloys, which includes deoxidizing theprincipal melt with magnesium and then mixing it with molten aluminum.

3. The method of making nickel alloys,

which includes mixing the principal melt With aluminum and utilizing theevolved heat to maintain the alloy at or above a pouring temperatureover a settling period, thereby giving impurities in the alloy time toseparate therefrom.

4. The method of making nickel alloys, which includes deoxidizing theprincipal melt, mixing the principal melt with aluminum. and utilizingthe evolved heat to maintain the alloy at or above a pouring temperatureover a settling period, thereby giving impurities in the alloy time toseparate therefrom.

5. The method of making nickel aluminum alloys, which includes pouringthe nickel melt onto the aluminum.

6. An alloy containing the elements which go to make up Monel metal andaluminum, containing from 1% to 10% of aluminum.

7. An alloy containing the elements which I go to make up Monel metaland aluminum, containing from 1% to 10% of aluminum and containingcarbon from .1% to .5%.

8. An alloy containing -80% nickel, 2040% copper, 110% aluminum, and0.252.5% manganese.

9. An alloy containing 50-80% nickel,

.2040% copper, 110% aluminum, 0.252.5%

manganese, and 01-05% carbon.

10. An alloy of nickel, copper and aluminum, wherein the content ofnickel is in excess of 50% and the content of aluminum is not less thanabout 3% and not more than 17 the predominant metal of the remainingcontent being copper.

less than the content of copper is not less than 18%, and the content ofaluminum is not less than about 3%, the three metals tent of aluminum isabout 4% to 5%, the.

predominant metal of the remaining content being copper.

13. An alloy of nickel, copper and aluminum, wherein. the content ofnickel is to 70% and the content of aluminum is 10% to 3%, thepredominant metal of the remaining content being copper.

14. An alloy of nickel, copper and aluminum, wherein the content ofnickel is in excess of 50% and the content of aluminum is not less thanabout 3% but is insufiicient to destroy the malleability of the alloyfor mechanical working, the predominant metal of the remaining contentbeing copper,

15. An alloy of nickel, copper and aluminum, wherein the content ofnickel is not less than 50% and the content of aluminum is between 1%and 17%, the remaining content consisting essentially of copper.

16. An alloy containing. 1%-17% of aluminum, the remainder consistingessentially ofnickel and copper with the nickel in excess of the copper,the copper being not less than 18%.

17. An alloy consisting essentially of 50%80% nickel, 20%10% copper, and1%10% aluminum.

18. An alloy consisting essentially of 50% 80% nickel, 20%40% copper,and 1%- 10% aluminum, together with carbon not in excess of .5%.

19.An alloy containing the elements which go to make up Monel metal andaluminum containing from 1% to 10% of aluminum, together with carbon notin ex- I cess of .5%. 11. An alloy of nickel, copper and aluminum,wherein the content of nickel is not- In testimony whereof I havehereunto set my hand.

PAUL D. MERTOA.

